Softball with great resilient coefficient

ABSTRACT

A softball associated with the game of softball comprises a core, an inner cover and an outer cover. The core is made by a mold and of either a cork material or a polyurethane material. The inner cover surrounds said core, being made of a material different from the core and selected from the group of a cork-type material and a polyurethane-type material. The outer cover surrounds both the core and the inner cover. The softball thus formed can sustain substantially constant hardness against variations in temperature and humidity. Further, by adjusting the ratio of thickness of the core and the inner cover, the softball can attain a higher coefficient of resilience as required.

FIELD OF INVENTION

The present invention relates softballs for softball gaming, and more particularly to a softball that is easy to make and can sustain substantially constant hardness against variations in temperature and humidity and has a great resilient coefficient. Further, by adjusting the ratio of thickness of the core and the inner cover, the softball can attain a higher coefficient of resilience as required.

DESCRIPTION OF THE PRIOR ART

As shown in FIG. 1, a softball of a conventional inner structure includes a core 10 and a cover 20 surrounding the core 10. The core is made by a mold and of a cork-type or a silk-cotton-type material. A softball thus made has the disadvantage of having non-uniform hardness over the ball surface. To remedy this fault, a core shell 30 formed by winding yarn strings around the core is applied first. The core 10 and the core shell 30 are then surrounded by the cover 20 to form a softball. The addition of a core cover 30 complicates the manufacturing process, and it also reduces the coefficient of resilience, leading to a less bouncing softball.

As shown in FIG. 2, a softball of another conventional inner structure includes a core 40 and a cover 50 surrounding the core 40. The core 40 is made by a mold and of a polyurethane-type material. Because of the polyurethane-type material, the softball is of uniform hardness and higher coefficient of resilience. Further, the structural simplicity, without a string-wound core shell, makes it is easy to make. However, since the polyurethane-type material is susceptible to variations in temperature and humidity, the hardness of the softball is not constant over a variety of environments.

SUMMARY OF THE INVENTION

Accordingly, the present invention provides a softball having a novel inner structure which is easy to make and can sustain substantially constant hardness against variations in temperature and humidity. Further, by adjusting the ratio of thickness of the core and the inner cover, the softball can meet a required coefficient of resilience.

To achieve the above objectives, a softball according to the present invention comprises a core, an inner cover and an outer cover. The core is made by a mold and of either a cork-type material or a polyurethane-type material. The inner cover surrounds said core, being made of a material different from the core and selected from the group of a cork-type material and a polyurethane-type material. The outer cover surrounds both the core and the inner cover. The softball thus formed can sustain substantially constant hardness against variations in temperature and humidity. Further, by adjusting the ratio of thickness of the core and the inner cover, the softball can meet a required coefficient of resilience.

DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross-sectional view of a softball of a conventional inner structure.

FIG. 2 is a cross-sectional view of a softball of another conventional inner structure.

FIG. 3 is a cross-sectional view of the first preferred embodiment of the present invention as a softball.

FIG. 4 is a cross-sectional view of the second preferred embodiment of the present invention as a softball.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The various objects and advantages of the present invention will be more readily understood from the following detailed description of preferred embodiments, when read in conjunction with the appended drawings.

As shown in FIG. 3, the first preferred embodiment of the present invention as a softball comprises a core 60, an inner cover 80 and an outer cover 70. The core 60 is of substantially spherical shape and is made of a predetermined cork-type material. Further, the core 60 is made by a mold. The inner cover 80 surrounds the core 60, and the inner cover 80 is made of a predetermined polyurethane-type material. The outer cover 70 surrounds the core 60 and the inner cover 70 to form a softball. The core 60 can also be made of a silk-cotton material instead.

As shown in FIG. 4, the second preferred embodiment of the present invention as a softball comprises a core 60, an inner cover 80 and an outer cover 70. The core 60 is of substantially spherical shape and is made of a predetermined polyurethane-type material. Further, the core 60 is made by a mold. The inner cover 80 surrounds the core 60, and the inner cover 80 is made of a predetermined cork-type material. The outer cover 70 surrounds the core 60 and the inner cover 70 to form a softball. The inner cover 80 can also be made of a silk-cotton material instead.

As indicated by the aforecited preferred embodiments, a softball according to the present invention is characterized by a core 60 surrounded by an inner cover 80. The core 60 and the inner cover 80 are respectively made of a cork-type material and a polyurethane material or vice versa. Although those materials are common internal materials of conventional softballs, the combination of those two types of materials makes possible a softball that is easy to make and can sustain substantially constant hardness against variations in temperature and humidity. Further, by adjusting the ratio of thickness of the core and the inner cover, the softball can attain a higher coefficient of resilience as required.

The present invention is thus described, and it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the present invention, and all such modifications as would be obvious to one skilled in the art are intended to be included within the scope of the following claims. 

1. A softball with a great resilient coefficient, comprising: a spherical core made of a predetermined cork material, said core being made by a mold; an inner cover surrounding said core, said inner cover being made of a polyurethane material; and an outer cover surrounding said core and said inner cover.
 2. A softball with a great resilient coefficient, comprising: a spherical core made of a predetermined cork material, said core being made by a mold; an inner cover surrounding said core, said inner cover being made of silk cotton; and an outer cover surrounding said core and said inner cover.
 3. A softball with a great resilient coefficient, comprising: a spherical core made of polyurethane material, said core being made by a mold; an inner cover surrounding said core; and an outer cover surrounding said core and said inner cover.
 4. The softball with a great resilient coefficient as claimed in claim 1, wherein, said inner cover being made of cork material.
 5. The softball with a great resilient coefficient as claimed in claim 1, wherein, said inner cover being made of silk cotton. 